I’m a customer of Dropbox many, many years, a paying customer, and was always happy about the service, as it is fast and easy to use. No problems … until now! Be aware … this will be a rant :/
But first a step back:
Nowadays it is normal to work with different classes of devices: stationary PCs, different types of laptops, tablets and also smartphones. You start writing a text on your laptop at home in the garden, have to interrupt it because of an appointment and continue writing on your tablet on your way, only to finish it at home on your PC, because it has started to rain. All of these used devices to write the text may have a different hard- and software configuration, but today we have synchronisation services like Dropbox, OneDrive, GoogleDrive and man others, which ensures that the same version of the text is available at all times at all devices.
To me it is obvious that software manufacturers cannot support every operating system, but I can expect that if they support a particular OS, they will do so on any hardware that the OS manufacturer also supports!